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<head><title>null -- the unique member of the empty class</title>
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<div><h1>null -- the unique member of the empty class</h1>
<div class="single"><h2>Description</h2>
<div>When it is the value of an expression entered into the interpreter, the output line doesn't appear. Empty spots in a list are represented by it.<p/>
It is the only member of the class <a href="___Nothing.html" title="the empty class">Nothing</a>, which strictly speaking, ought to have no members at all.<p/>
An <a href="_if.html" title="condition testing">if</a> expression with no <a href="_else.html" title="condition testing">else</a> clause returns <a href="_null.html" title="the unique member of the empty class">null</a> when the predicate is false.<p/>
Various routines that prepare data for printing convert <a href="_null.html" title="the unique member of the empty class">null</a> to an empty string.<table class="examples"><tr><td><pre>i1 : x = {2,3,,4}
o1 = {2, 3, , 4}
o1 : List</pre>
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<tr><td><pre>i2 : net x
o2 = {2, 3, , 4}</pre>
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<tr><td><pre>i3 : toString x#2
o3 = null</pre>
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<tr><td><pre>i4 : peek x
o4 = {2, 3, null, 4}</pre>
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<div class="waystouse"><h2>For the programmer</h2>
<p>The object <a href="_null.html" title="the unique member of the empty class">null</a> is <a href="_null.html" title="the unique member of the empty class">null</a>.</p>
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